Aurora Borealis
Des Moines, Iowa, USA

Some of the most famous light shows in the world are called auroras or, more commonly in the Northern Hemisphere, the "Northern Lights." What causes these spectacular displays? Streams of particles with electric charge are continually leaving the Sun and traveling through the Solar System. As these particles approach the Earth, some of them are channeled by the planet's magnetic field toward the North and South Poles. When these particles collide with atoms in the Earth's atmosphere, the atoms in the atmosphere are excited give off light of a particular color tied to that type of atom.